A364758 G.f. satisfies A(x) = 1 + x*A(x)^4 / (1 + x*A(x)).

1, 1, 3, 14, 76, 450, 2818, 18352, 123028, 843345, 5884227, 41650479, 298352365, 2158751879, 15754446893, 115830820439, 857147952469, 6379136387303, 47715901304501, 358529599468636, 2704884469806606, 20481615947325089, 155605509972859999

Offset

0,3

Links

Table of n, a(n) for n=0..22.

Formula

a(n) = (1/n) * Sum_{k=0..n-1} (-1)^k * binomial(n,k) * binomial(4*n-3*k,n-1-k) for n > 0.

Prog

(PARI) a(n) = if(n==0, 1, sum(k=0, n-1, (-1)^k*binomial(n, k)*binomial(4*n-3*k, n-1-k))/n);

Crossrefs

Cf. A090192, A106228, A364759.

Cf. A364747.

Sequence in context: A223026 A371434 A364477 * A353253 A198702 A198621

Adjacent sequences: A364755 A364756 A364757 * A364759 A364760 A364761

Keyword

nonn

Author

Seiichi Manyama, Aug 05 2023

Status

approved